Field of the Invention
The present invention relates to control for reducing (correcting) an image blur (or for an image stabilization) in tilt imaging.
Description of the Related Art
As the tilt and shift photographing (tilt and shift imaging) using a single-lens reflex camera etc., the tilt imaging uses an optical system (imaging lens) having an optical axis tilted to a normal of an imaging surface. The tilt imaging can widen or narrow a depth of field (in-focus range). The image stabilization is necessary even in the tilt imaging similar to the normal imaging, due to a vibration of an optical system, such as a manual vibration (camera vibration). For the image stabilization, a shift lens (shift lens unit) as part of the optical system or an image sensor disposed on an imaging surface (which are collectively referred to as a “shiftable unit” hereinafter) may be shifted from the optical axis of the optical system or a normal (line) of the imaging surface.
Japanese Patent Laid-Open No. 2008-35308 discloses a tilt and shift photographing method configured to shift an image sensor by an amount necessary for the tilt and shift photographing and to provide an image stabilization by shifting the image sensor using a shifted position of the image sensor as a center in accordance with a camera vibration in shift imaging in the tilt and shift photographing.
An object surface (in-focus plane on the object side) is not parallel to the imaging surface in the tilt imaging. When the shiftable unit is shifted for the camera vibration in a direction parallel to the imaging surface, the image blur can be corrected but the defocus occurs.